FJ may refer to:
Places Fiji (ISO 3166-1 alpha-2 country code) .fj, the country code top level domain (ccTLD) for Fiji Fijian language (ISO 639-1 language code) Fujian, a province of China
Vehicles FJ Fury, an early Cold War fighter aircraft of the US Navy Flying Junior, a sailing dinghy Holden FJ, an Australian car Jeep FJ, a compact delivery van Toyota FJ Cruiser, a sport utility vehicle Yamaha FJ, motorcycle
Science and mathematics The FASEB Journal, a scientific journal of experimental biosciences Femtojoule (fJ), an SI unit of energy equal to 10−15 joules Fritz John conditions, conditions in optimization problems
Media FictionJunction, a J-pop group The FJ Holden, an Australian film
Military , German paratroopers , a military rank of the Bundeswehr FJ ABM, an anti-ballistic missile Young Force (), the former youth wing of the Fuerza Nueva Youth Front (), a Spanish terrorist organization
Aviation Fiji Airways (IATA code) Williams FJ33 and FJ44, families of turbofan jet engines
Other uses FJ Management, an American corporation FJ Reitz High School, a public high school in Evansville, Indiana Formula Junior, an auto racing class Sony Vaio FJ, a mid-2000s series of laptops Fulbright & Jaworski, former United States law firm
See also FJD (disambiguation) FJS (disambiguation)